scope:

The presence of a nozzle in a pressure vessel creates a region of increased localized stress in the vicinity of the opening. The purpose of this study is to provide experimental data which show the general state of stress in nozzles. The study was made on three types of outlets contained in cylindrical shells: (a) five hot-formed contoured nozzles, (b) four insert nozzles, and (c) one juncture reinforced by an annular pad The nozzles differed in size, and in the amount and distribution of the reinforcing material around the outlets. Internal pressure and various external loads to the branch pipe were applied.